The goal of this program is to train MD and PhD postdoctoral fellows in biomedical research as it applies to Blood Coagulation and Vascular Biology. We offer a multi-disciplinary program that consists of didactic instruction, seminars and supervised research. Important elements of the curriculum are supervision by faculty advisors, formal course work, interactions between trainee and the faculty, and interactions between the trainee and peers. Dr. Bruce Furie is the Program Director and Drs. Robert Flaumenhaft and Kenneth Bauer are the Associate Program Directors. Faculty of the program, members of the Dept of Medicine at Beth Israel Deaconess Medical Center and Harvard Medical School, share a scientific interest in blood coagulation and vascular biology. MD trainees are selected from about 350 applicants each year. Only those applicants with an explicit commitment to a career in academic medicine are selected. This training plan is integrated into the hematology training program. MD trainees choose between two tracks. The Physician-Scientist Track consists of a minimum of two years of supervised bench research and didactic instruction after completion of the major portion of hospital-funded clinical subspecialty training. The Clinical Investigator Trac prepares participants for a career in clinical investigation in the areas of blood coagulation and vascular biology. We also receive approximately 300 applications per year from candidates with a PhD degree or physicians applying solely for research training. The design of the program takes into account (a) the need for physicians to acquire knowledge of advances in molecular and cell biology; (b) the need for an extended training experience to allow fellows to develop sophistication in modern biomedical research; (c) the need for PhD scientists to understand the pathobiology of the vascular system. This grant, funded for the past 15 years, is a continuation of T32 HL07437, which had been active at Tufts Medical Center for 20 years. During the past fifteen years, this application has supported 48 trainees. Of 11 MD or MD/PhDs, 6 are pursuing academic careers, most with research support, 2 are in the pharmaceutical industry, 2 are in various aspects of training, and 1 is in clinical practice. Of 37 PhDs, 19 are pursuing academic careers, 9 are in the pharmaceutical industry, 1 is a scientific editor, 1 was lost to follow-up, ad 7 remain in training. This training program has proved exceptionally successful, and has been greatly enriched by its move to Harvard Medical School.